V T B 1

v i s i t

M I C R O P H O N E

o u r w e b s i t e a t
DISTRIBUTED BY PMI AUDIO GROUP
23775 Madison Street Torrance, California 90505 USA STUDIO PROJECTS Place Stamp Here

P R E A M P L I F I E R

s t u d i o p r o j e c t s u s a. c o m
INSTRUCTION BOOK CONTENTS
What is Studio Projects....2 Why do I need a microphone preamplifier...3 Description, Care....3 Connecting up....3 Feature Control Descriptions...4 Specifications....4 Circuit Topology....5 Problems.6 Origins and manufacture...6 Declarations of conformity...6 Troubleshooting....6 User Specified Settings...9
Studio Projects is manufactured and marketed under the direction of:

WHAT IS STUDIO PROJECTS?

Studio Projects is a technology company. Armed with the idea that quality products do not have to be expensive, Studio Projects set out to design and offer quality audio products at a price that is affordable to most users. As a small sized company with lower expenses than its competitors, Studio Projects is able to pass extra savings onto the end user, and provide a high level of quality at a very competitive price. When Studio Projects introduced its "C" Series microphones in 2001, both end users, reviewers, and audio professionals acclaimed the quality and sound as nothing short of amazing. With the introduction of the new "B" Series microphones in 2002, Studio Projects has pushed the envelope even further supporting its quality and performance for an affordable price. Now we are entering the electronic market and offer our first electronic product, the VTB1. This unique product will offer the best possible quality and feature set in its price class. We hope you will enjoy your new VTB1 as much as we have enjoyed making it for you.
PMI AUDIO GROUP 23775 Madison Street Torrance, CA 90505 voice (310) 373-9129 facsimile (310) 373-4714 toll-free USA (877) 563-6335 Email info@pmiaudio.com
WHY DO I NEED A MICROPHONE PREAMPLIFIER
A microphone preamplifier takes audio signals from any microphone (XLR socket), musical instrument or high level source (1/4 inch jack sockets), and amplifies them up to 'line' level; that is, from a few millivolts, up to about a volt. The phantom power supply (push-button switch) provides power to capacitor microphones. Dynamic or ribbon microphones should be used with the phantom power turned off, then full advantage can be taken of the extreme low noise performance of this preamplifier. Before you connect anything to your new VTB1, be sure to turn down all of the input and output levels. Plug in the supplied power adaptor. Be sure to plug the barrel connector into the VTB1 first, and then plug it into an electrical supply outlet. Using a good quality XLR cable, connect your microphone to the VTB1 XLR input on the back of the VTB1. Using either the XLR, or the 1/4" output, hook this into your recorder, computer card, or whatever you are recording or playing into. Be sure to turn the 48V phantom power switch to on if you are using a mic that requires phantom power. Wait at least 60 seconds for the power to charge your mic before turning up any gains. Set the meter selection switch to input, and adjust the GAIN control to get a meter reading within the 0 to +8 range. Then turn up the output control to feed your recorder. When changing microphones or powering down, be sure to turn down both input and output levels first. Then turn off the 48V power and wait 60 seconds. Then it will be safe to turn unplug the unit, or to change microphones. Use this method of powering up and down each time you use the VTB1. It is best to wait about 30 minutes before using the VTB1 to let the internal tube heat up to get the best out of the unit. CAUTION. When using UNBALANCED MICROPHONES DO NOT USE PHANTOM POWER, It could damage the microphone and will certainly cause noise on the output. An LED light shows on the front panel as a warning that the phantom power is turned on.

DESCRIPTION / CARE

Your new VTB1 is a sturdy piece of equipment. It should not require much care other than common sense. The VTB1 is built to stand up to the demanding use of the professional. If you follow a few simple procedures, it will provide you with years of trouble free service. 1) Keep the VTB1 in a dry dust free environment 2) Avoid blocking the air vents on the side panels 3) Never use an incorrect power supply other than the correct voltage and amp rating

CONNECTING THE VTB1

The VTB1 can be used in many applications, from recording to live applications. This section will help you get your new VTB1 connected as well as explain the connections on the VTB1 to help you get the most from your new unit.
FEATURE CONTROL DESCRIPTION
This outline will familiarize you with all of the features and what they do.

VTB1 SPECIFICATIONS

Maximum Gain: Mic In to Bal Out: 72dB (60dB preamp gain, 12dB output gain) Line In to Bal Out: 42dB (30dB preamp gain, 12dB output gain) Distortion/Noise (THD + Noise): -20dBu input-Mic; 0dBu input-Line Both measured at +15dBu output Mic or Line In to Bal or Line Out: <0.0015% (Blend set full CCW- no tube) Mic EIN: -128dBu (150 ohm source, 60dB gain) Frequency Response (20-20kHz, ref 1kHz): -20dBu input, +15dBu output Mic In to Bal Out: +0 /-0.25 dB 0dBu input, +15dBu output Line In to Bal Out: +0 /-0.5 dB Phase response (20-20kHz, either input): <+/- 15 degrees Input Impedance: Mic Input (Rear switch in 200 ohm position): 2000 ohms Mic Input (Rear switch in 50 ohm position): 300 ohms Line Input (Front panel TRS jack): 1.5 meg ohms Output Impedance: Male-XLR Balanced Output: 100 ohms (50 ohms each leg) TRS Line Out: 300 ohms (Impedance Balanced) Insert Jack (TRS): Nominal level approx 0dBu Located between SS preamp stage and tube/output stage Tip=Send: 50 ohms output impedance Ring=Return: 7500 ohms input impedance

CIRCUIT TOPOLOGY

Mic Preamp: Discreet, current-source fed, paralleled-transistor balanced input stage feeding a bipolar opamp balanced-unbalanced converter. Dual feedback design for low distortion performance. 2-Stage design for increased performance; transistor stage provides up to 45dB gain, 2nd stage contributes up to 15dB gain. Line Input: FET-input opamp buffer with hi input impedance to avoid pickup loading when used as an instrument preamp. 2nd stage provides adjustable gain from 10dB to 30dB, constant hi-impedance is maintained. Hi-pass filter: 75Hz hi-pass filter for low-freq wind and rumble elimination (3-pole filter @-18dB/oct). Tube Blend: Constant-level blend control allows the user to smoothly change from an all solid-state path to a tube-based preamp. This allows the user to add the desired amount of tube sound to the signal without having to deal with complicated "tube drive" controls and such. Alternately, it allows the user to use only the solid-state portion of the preamp to get a very low distortion, un-colored sound when desired.
Tube Stage: 12AX7 vacuum tube with DC filament supply for minimum hum and noise. 1st half of tube is operated as a hi-gain amplifier stage, 2nd half operates as a cathode follower to minimize loading of the first stage. A low-voltage plate supply is used to create a "starved-tube" condition for enhanced sound. Output Stage: Bipolar, lo-noise, hi output-current opamp used for best performance. 1st stage is used to provide additional gain (6dB) and drives the Line out jack and Pin-2 of the balanced out. The 2nd stage provides signal inversion and drive for Pin-3 of the balanced output (effectively an additional 6dB gain). For best Tube-Sound results: The tube operates best when provided with a solid signal. The best way to accomplish this is to use the on-board metering to set the internal levels. Press the Meter Select switch IN, the meter will now display the signal level within the preamp, just before the tube stage. Adjust the GAIN control to get a meter reading within the 0 to +8 range. With the OUTPUT control at "0", start turning the BLEND control clockwise until the desired sound is heard. Depending on the source material, more or less BLEND will be needed. If the output level is too high or low for your following equipment, adjust the OUTPUT control to compensate. This wont change the sound of the blended signal, just the overall level.

PROBLEMS

Studio Projects electronics are extremely resistant to physical damage, but if the unit fails to work after being dropped, it should be returned in adequate packing to the supplier. A double test and inspection system means that manufacturing faults are non-existent but should any fault occur, it will be repaired (or replaced) free of charge except where the fault has been caused by physical damage. (SEE WARRANTY INFORMATION)

TROUBLESHOOTING

1) The microphone doesn't work! Have you got something plugged into the INSTRUMENT input or is the mic/line set incorrectly? (this can disable the microphone input) Is the phantom power on? (capacitor microphones). If there is indication on the VU LED, is the output volume control turned down? 2) Got signal going through but no output? Is there enough signal? Use plenty of drive. Is the output gain control turned up, and do you have a properly working monitor system? 3) I dont get any power! Is the supplied power supply plugged in correctly? Make sure the barrel connector is pushed all the way into the socket, and be sure you have available power to the supply.

ORIGINS AND MANUFACTURE

Studio Projects Electronics are entirely designed in the USA. They are manufactured in China by 797 Audio to a specification created by Studio Projects, Torrance, California. All Studio Projects electronics are inspected and tested at the factory, then inspected and tested again at PMI Audio Groups facility prior to shipping. Studio Projects electronics meet the requirements of electronic equipment sold both in the USA, Canada, and the European Union. All Studio Projects products are CE Approved, and all power supplies are UL rated.
DECLARATION OF CONFORMITY
This analog audio processing equipment conforms to the standards and requirements of the European Economic Community. The EC Harmonized standards that have been applied are; a) Electrical equipment (safety) Regulations 1994 (S.I. 1994/3260) b) Electromagnetic Compatibility Directive (89/336/EEC) incorporating (S.I. 1992/2372)
STUDIO PROJECTS LIMITED WARRANTY
THIS PRODUCT IS FOR PROFESSIONAL USE ONLY
PMI Audio Group warrants that all products will be free from defects in material or workmanship: A: For a period of (1) one year from the date of purchase (hereinafter the labor warranty period), PMI Audio Group will repair or replace this Product if determined to be defective. After the expiration of the labor warranty period, the Purchaser must pay labor charges. B: In addition, PMI Audio Group will supply, at no charge, replacements for defective parts for a period of (one year) from the date of purchase. During the labor warranty period, to repair the Product, Purchaser must return the defective Product, freight prepaid, or deliver it to PMI Audio Group Service Center. The product to be repaired is to be returned in either its original carton or a similar package affording an equal degree of production. PMI Audio Group will return the repaired Product freight prepaid to the Purchaser. PMI Audio Group is not obligated to provide Purchaser with a substitute unit during the warranty period or at any time. rate. No repair or replacement by Purchaser of any Product or part thereof shall extend the warranty period as to the entire Product. The specific warranty on the repaired part only shall be in effect for a period of ninety (90) days following the repair or replacement of that part or the remaining period of the Product warranty, whichever is greater. 2. Exclusive Remedy: Acceptance: Purchasers exclusive remedy and PMIs sole obligation is to supply (or pay for) all labor necessary to repair any product found to be defective within the warranty period and to supply, at no extra charge, new or rebuilt replacements for defective parts. If repair or replacement fails to remedy the defect, then and only in such an event, shall PMI exchange to Purchaser a new or reconditioned unit. Purchasers failure to make a claim as provided in paragraph 1 above or continued use of the product shall constitute an unqualified acceptance of such Product and a waiver by Purchaser of all claims thereto. 3. Exceptions to Limited warranty: PMI shall have no liability or obligation to Purchaser with respect to any Product subjected to abuse, improper use, negligence, accident, modification, failure of the end-user to follow the operating and maintenance procedures outlined in the users manual, attempted repair by non-qualified personnel, operation of the unit outside of the published environmental and electrical parameters, or if such products original identification (trademark, serial number) markings have been defaced, altered, or removed. PMI excludes from warranty coverage, Products sold AS IS and/or WITH ALL FAULTS and excludes used products which have not been sold by PMI to the Purchaser. PMI also excludes from warranty coverage consumables such as fuses and batteries, etc. 4. Proof of purchase: The dealers dated bill of sale must be retained as evidence or the date of purchase and to establish warranty eligibility

CONDITIONS

1. Notification of claims: Warranty Service: If Purchaser discovers that the Product has proven defective in material or workmanship, then written notice with an explanation of the claim shall be given promptly by Purchaser to PMI but all claims for warranty service must be made within the warranty period. If after investigation PMI determines that the reported problem was not covered by the warranty, Purchaser shall pay PMI for the cost of investigating the problem at its then prevailing time-and-materials

DISCLAIMER OF WARRANTY

EXCEPT FOR THE FORGOING WARRANTIES, PMI HEREBY DISCLAIMS AND EXCLUDES ALL OTHER WARRANTIES, EXPRESS OR LIMITED, INCLUDING, BUT NOT LIMITED TO ANY/OR ALL IMPLIED WARRANTIES OF MERCHANT ABILITY, FITNESS FOR A PARTICULAR PURPOSE AND/OR ANY WARRANTY WITH REGARD TO ANY CLAIM OF INFRINGEMENT THAT MAY BE PROVED IN SECTION 2-312(3) OF THE UNIFORM COMMERCIAL CODE AND/OR IN ANY COMPARABLE STATE STATUE. PMI HEREBY DISCLAIMS ANY REPRESENTATIONS OR WARRANTY THAT THE PRODUCT IS COMPATIBLE WITH ANY COMBINATION OF NON-PMI AUDIO PRODUCTS PURCHASER MAY CHOOSE TO CONNECT TO THE PRODUCT.

OWNERS REGISTRATION CARD

T O B E C O M P L E T E D AT T I M E O F P U R C H A S E Name _____________________________________________ Date of Purchase ____________________________________ Serial Number ______________________________________ Dealers Name ______________________________________

LIMITATION ON LIABILITY

THE LIABILITY OF PMI, IF ANY, AND PURCHASERS SOLE AND EXCLUSIVE REMEDY FOR DAMAGES FOR ANY CLAIM OF ANY KIND WHATSOEVER, REGARDLESS OF THE LEGAL THEORY AND WHETHER ARISING IN TORT OR CONTRACT, SHALL NOT BE GREATER THAN THE ACTUAL PURCHASE PRICE OF THE PRODUCT WITH RESPECT TO WHICH SUCH CLAIM IS MADE. IN NO EVENT SHALL PMI BE LIABLE TO PURCHASER FOR ANY SPECIAL, INDIRECT, INCIDENTAL, OR CONSEQUENTIAL DAMAGES OF ANY KIND INCLUDING, BUT NOT LIMITED TO, COMPENSATION, REIMBURSEMENT OR DAMAGES ON ACCOUNT OF THE LOSS OF PRESENT OR PROSPECTIVE PROFITS OR ANY OTHER REASON WHATSOEVER.
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Specifications and model numbers are subject to change without notice
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MIX Electronic Musician EQ Home Recording Pro Audio Review Recording Pro Sound News

Studio Projects LSM Quick Start Guide
ello and thank you for choosing the Studio Projects LSM dual output condenser microphone the high fidelity, ultra portable, colorful and uniquely cool choice for all your professional audio and communication miking needs. High Fidelity you say? We think you'll agree. The 34mm Von Braunmuhl and Weber-style cardioid transducer, coupled to a discrete JFET impedance converter with a high SPLhandling output circuit insures that the LSM will effectively receive your acoustic source and change it to electrical and digital impulse with due care, all the while insuring that the outermost parameters of the circuitry itself do not interfere unduly with the signal sanctity of your source. Designed with the convenience of the ubiquitous USB mini plug and a conventional three-pin mini XLR output, the LSM gives you two distinct ways to route your signal, as well as an integrated yoke, which means the LSM can stand freely upon a desktop, or mount to any
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variety of mic stand, all in a classic - yet completely fresh style. With regards to portability, the Studio Projects LSM, as a large capsule mic, is unparalleled. Fitting neatly in a laptop bag pocket, or even in your shirt pocket, the LSM, with its petite form factor is ideal for taking on the road wherever you go. This Quick Start Guide is your ticket to bypassing all that boring stuff in the typical user's manual and getting right to the heart of things: Hooking up new gear! So let's get to it. Unpacking and setting up the LSM Microphone: 1. Ah yes: A new microphone. How cool is this! Take out the mic and let's have a look at this thing. 2. For desktop use, adjust the integrated stand yoke so that the microphone is leaning back slightly, angled up toward your face - akin to the tripod configu-

LSM in Desktop Mode

ration of an astromech droid. The two knobs on either side of the microphone are right-hand thread. To loosen, twist the left knob away from you and the right knob towards you - this is the standard "lefty-loosey, rightytighty" mnemonic imparted by technically-inclined grandfathers. If the knobs are on there really tight, simply hold the stand yoke with one hand while tipping the microphone up and back away from you with the other.
3. To attach the LSM to a mic stand, there are 5/8-27 threads on the bottom of the stand yoke. That's a fiveeights of an inch diameter hole with twenty-seven
threads per inch (TPI), in case you were wondering. Anyhow, the LSM will thread onto the stand the same as any other mic clip or shock mount. Ta-da! Note that the yoke can be adjusted perpendicularly to the body of the mic, for perfect orientation on a broadcast mic boom as well.
There are two cables that ship with every LSM Microphone: 1. USB mini cable 2. Mini XLR Female To Standard XLR Male - not to be confused with the "Typical Male XLR", which tends to leave its shoes lying about in every room. If you wish to use the XLR output, here's what to do: 1.Plug the small end of the xlr cable into the round plug on the reverse side of the LSM.
2. Insert the other end of the xlr cable into a +48 volt phantom power equipped microphone preamp input. This can be the input to a mixing console, a dedicated mic preamp, such as our Studio Projects VTB-1, or any of the myriad digital audio interfaces with suitable p48 inputs.

Studio Projects VTB-1

Note: Remember to make sure that the 48v button is engaged on your preamp, or the circuitry of the LSM will not power up.
Another Note: Of course you will remember to have the input volume down while plugging the mic in, so as not to make your speaker cones jump across the room, or potentially cause a bunch of earsplitting feedback.

3. Adjust the input gain to a suitable level and say something into the mic, such as the following palindrome: "Stop, Syrian, I start at rats in airy spots!" And there you go. Pretty cool, huh?
Now, if ye wish to employ the USB output - and I'm sure you do, please adhere to the following steps: 1. Insert the small end of the included mini USB cable into the USB plug on reverse side of the LSM, just above the round, three-pin xlr thingy. 2. Plug the other end of the USB cable into a computer, be it Mac or PC. 3. Select "USB Microphone" as your input source, bring up the volume and say something into the mic, such as the following palindrome: "Are we not drawn onward, we few, drawn onward to new era?" Adjust input volume as needed. 4. If you are at all confounded by step number 3 above, don't worry - we will cover that in greater detail now. Note: For Windows users with audio recording software, we highly recommend that you install ASIO4ALL as your WDM driver for the LSM microphone. This driver can be found at www.asio4all.com. It is easy to install and configure: simply follow the instructions in the downloadable pdf user manual found on the ASIO4ALL website and adjust as needed for best performance on your system.
Setting up the LSM as your default recording device, Windows XP: 1. Go to the start menu (lower left-hand corner of the screen) and open up the control panel 2. Select sounds and audio devices 3. Select the Audio tab 4. Under Sound recording, select USB microphone in the drop-down menu, Default device: 5. Adjust volume of the microphone in Sound Recording by clicking the Volume button beneath the Default device: drop-down You are now good to go. Setting up the LSM as your default recording device, Windows Vista: 1. In the Start menu search, type in "Sound". 2. Select sound from the search results of the start menu under Programs
3. Click on the Recording tab in the Sounds menu and scroll down if needed until you locate Microphone. If the LSM is the only USB microphone plugged in to the computer, it will say "1- USB Microphone Working". 4. Mouse over and double-click in the field around the word Microphone to bring up the Microphone Properties menu. 5. In the General tab, type in "LSM". 6. Click on the Levels tab and adjust volume as needed. You are now up and running. Setting up the LSM as your default recording device, Windows 7: 1. Well, it's pretty similar to the Vista setup, actually. The only caveat being, when you type in "Sound" in the start menu search field, you select sound under Control Panel, rather than Programs. You'll see. Other than that, it's basically the same as Vista.

You are styling. Nothing's going to stop you now.
Setting up the LSM as your default recording device, Mac OS X: 1. Connect LSMto Mac. 2. Mac OS should automatically detect USB LSM. 3. If Mac does not automatically detect mic, then go to System Preferences and select Sound in the Hardware list 4. Select Input and select USB.
If you run into any issues with the setup of the LSM and you're completely lost, or nothing's working as it should - just relax, chin up, make a cup of tea and give us a call at 310-323-9050, or in the UK +44 (0)700. By email, contact us at contactus@studioprojects.com. We are happy to help. Our U.S. facility is located in Southern California and we are open Monday through Friday, normal banker's hours. There is a good chance that you will get one of us on the phone before 9 a.m. or after 5 p.m. most business days as well. Otherwise, enjoy the mic, record a lot, wash behind your ears and remember to wear a hat if it's cold outside. Also, if you are using the LSM on a podcast or a recording project that you would like to share with us - by all means, let us know. Additionally, we may want to link to it on our site. Is anybody still reading this? Hellooo! Anyway, thank you very much for buying our gear, whoever you are. Enjoy! Check our website for updates and videos about our products, including the LSM at www.studioprojects.com
2010 PMI AUDIO GROUP. ALL RIGHTS RESERVED. STUDIO PROJECTS IS A REGISTERED TRADEMARK OF PMI AUDIO GROUP.
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